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Press Release

Former Sioux City Wastewater Treatment Plant Superintendent Sentenced to Federal Prison for Violating the Clean Water Act

For Immediate Release
U.S. Attorney's Office, Northern District of Iowa
Rigged Environmental Testing for Years

The former Superintendent of the Sioux City Wastewater Treatment Plant, who conspired to cheat on environmental testing at the plant, was sentenced on April 1, 2021, to three months in federal prison.

Jay Earnest Niday, age 63, from Sergeant Bluff, Iowa, received the prison term after a October 6, 2020 guilty plea to one count of conspiracy and one count of knowingly falsifying, tampering with, and rendering inaccurate a monitoring device or method required to be maintained under the Clean Water Act.

The evidence at Niday’s guilty plea and sentencing hearings showed that Niday was employed as the Superintendent of the Sioux City Wastewater Treatment Plant (WWTP).  The WWTP is a large regional sewage treatment plant for wastewater from industrial, commercial, and residential sources throughout Siouxland, including Sergeant Bluff, Iowa, South Sioux City, Nebraska, North Sioux City, South Dakota, and Dakota Dunes, South Dakota.  The WWTP’s more than 20 industrial users produce a large volume of high-strength wastewater.  Under a Clean Water Act (CWA) permit, the WWTP was required to treat wastewater before discharging it into the Missouri River, which has heavy local recreational use.  Between March 15 and November 15 each year, when public use of the Missouri River was at its highest levels, the WWTP was also required to disinfect its wastewater to remove potentially dangerous human pathogens, including fecal coliform bacteria or E. coli.

The WWTP treated its wastewater with liquid chlorine, which kills bacteria but is potentially toxic to aquatic life.  The WWTP’s permit required the WWTP to periodically test its wastewater not only for the presence of fecal coliform bacteria or E. coli, but also total residual chlorine (TRC) levels, to ensure that the Missouri River was not polluted.      

Beginning no later than 2011, and continuing until at least June 2015, Niday and others knowingly withheld from the Iowa Department of Natural Resources (IDNR) serious problems with the WWTP’s new treatment process, known as “the MLE process.”  Niday and others concealed this fundamental problem with the MLE process from the IDNR.

Niday and others knew that the WWTP did not work properly and could not consistently disinfect the millions of gallons of wastewater that the WWTP was discharging into the Missouri River each day.  In March 2013, an engineering firm prepared a “draft master plan” contemplated under a $1 million contract with the City and provided it to Niday and another person.  The draft master plan discussed the disinfection problems at the WWTP at length and concluded the WWTP’s treatment process could not provide adequate disinfection of the WWTP’s influent given the apparently high toxicity in its significant industrial users’ effluent.  Instead of following the recommendations in the draft master plan, Niday instructed the engineering firm to not finalize the report.

Niday and his coconspirators employed a fraudulent testing procedure that ensured the WWTP would always pass its effluent tests for fecal coliform, E. coli, and TRC.  Specifically, early in the morning on testing days for bacteria, Niday and a subordinate manager, Shift Supervisor Patrick Schwarte, instructed first‑shift operators at the WWTP to increase the rate of liquid chlorine supplied to the wastewater.  After an hour or two passed, and an artificially high level of chlorine was fully mixed into wastewater, they ordered the WWTP’s first-shift operators to use hand-held colorimeters to gauge the levels of chlorine.  Only when the colorimeter “maxed out” would the Superintendent take a sample for fecal coliform or E. coli.  This fraudulent procedure allowed for the chlorine in the wastewater to reach sufficient concentrations to avoid showing elevated levels of fecal coliform or E. coli, which would violate the WWTP’s CWA permits.  The WWTP never reported any exceedances of its CWA permit limits for bacteria or residual chlorine after July 2012.

The liquid chlorine rate was increased from about 2.5 gallons per hour, to somewhere between 70 to 120 gallons per hour, for up to two hours. On non-testing days, WWTP employees maintained the chlorine feed rate at minimal levels, well below the designed feed rate of the WWTP and at a rate clearly insufficient to ensure the WWTP consistently and adequately disinfected its wastewater, as the WWTP’s CWA permits required.  Then, in the afternoon on fecal coliform or E. coli testing days, well after the high amounts of chlorine had dissipated from the WWTP’s chlorine contact basin, and when an insufficiently low rate of liquid chlorine was supplied to the basin, Niday and Schwarte would test again for TRC.  In the afternoon, they were certain the TRC would pass, because only a minimal rate of liquid chlorine was supplied to the chlorine contact basin at that time.  Again, this minimal rate was clearly insufficient to ensure the WWTP consistently and adequately disinfected its wastewater, as required.

Niday was sentenced in Sioux City by United States District Court Chief Judge Leonard T. Strand.  Niday was sentenced to three months’ imprisonment and fined $6,000.  He must also repay $2,500 in court-appointed attorney fees and serve a two-year term of supervised release after the prison term.  There is no parole in the federal system.

“Jay Niday deliberately worked with others to cheat on environmental tests, knowing he was polluting the Missouri River,” said Acting United States Attorney Sean R. Berry.  “His actions not only put recreational users of the river at risk, but also endangered the river’s aquatic life.  Niday’s blatant disregard for the law, the safety of the community, and his reprehensible treatment of a vital waterway was outrageous.”

“By intentionally tampering with the disinfection processes at the Sioux City Wastewater Treatment Plant, Jay Niday placed the community and its natural resources in jeopardy of sustaining significant environmental damage,” said Special Agent in Charge Lance Ehrig of EPA’s Criminal Investigation Division for Iowa.  “Today’s sentencing demonstrates that such violations will be vigorously prosecuted.”

“Jay Niday knowingly manipulated data at a wastewater treatment plant that received millions of dollars in U.S. Environmental Protection Agency state revolving funds,” said Daniel Hawthorne, Special Agent in Charge of the EPA Office of Inspector General’s Western Region Field Office.  “This sentencing fulfills the

OIG’s commitment with our law enforcement partners to ensure that falsifying data and undermining the integrity of taxpayer dollars will not be tolerated.”

Niday was released on the bond previously set and is to surrender to the Bureau of Prisons on a date yet to be set.

The case was prosecuted by Assistant United States Attorneys Timothy L. Vavricek and Matthew J. Cole and investigated by the Environmental Protection Agency, Criminal Investigation Division, the Environmental Protection Agency, Office of Inspector General, and the Federal Bureau of Investigation. 

Court file information at

The case file number is 20-CR-4081-LTS.

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Updated April 2, 2021

Public Corruption